"We've already flashed to a time when Patsy's drooling and propped up in a wheelchair with a drip attached to a vodka bottle," she explained.

"Her and Eddy were about 102... No matter how badly Jennifer and I decay, we could carry on playing the characters forever [and] June Whitfield [Eddy's mother] seems to be getting younger all the time."

The 66-year-old actress also confessed that she shares some traits with her flamboyant, chain-smoking character.

"I only have maybe five a day," she said. "But playing Patsy has put me in a cage that makes me look like I smoke like an old wizard.

"I drink a fraction of what she does but I'm a bit like her. I don't have her vicious language but I adore her."